A small (grapefruit-sized) fully integrated, automated mechanical heart- lung system will be developed which will perform all the hemodynamic and blood gas exchange functions of the current large, complex extracorporeal cardiopulmonary by-pass (pump-oxygenator) systems. Incorporated within the proposed new device is a pulsatile flow, bladder type pump-reservoir in which is deployed a blood-on-the-outside/gas-on-the-inside hollow fiber membrane oxygenator. The highly efficient, thromboresistant, siloxane gas transfer membrane technology recently developed by the proposing scientists to produce the successful intra-vascular oxygenator (IVOX) will be modified/adapted to be applicable to the proposed new pump oxygenator. The objective of this project is to simplify, miniaturize, integrate, and automate the current extracorporeal cardiopulmonary by- pass perfusion system, thus making it fully portable, more blood compatible, safer, and more effective. If successful, the device could find widespread use in replacing the present cardiopulmonary by-pass systems used in many open-heart surgery cases and in most extracorporeal perfusion systems used for prolonged ECMO, ECLA, ELS, or ECCO2R, emergency life support perfusion systems, or for long term support of patients in cardiorespiratory failure. In the proposed Phase I of this R & D project the proposing scientists will: 1) produce and solidify the device design and materials concepts, 2) fabricate prototype devices, and 3) carry out engineering bench tests and ex vivo experimental animal perfusions to assess the performance characteristics and feasibility of the proposed unique new device. If this proposed Phase I study demonstrates feasibility, Phase II will be proposed and undertaken to optimize and fully evaluate the new device, preparing it for ultimate (Phase III) clinical trials.